Tilt switch with flat spring centering means

ABSTRACT

A switch having a tiltable actuator for pivoting a switch blade about a pivot terminal post in a make and break movement with respect to a pair of associated terminal contacts. A flat spring engages a cooperating flat portion on the bottomside of the actuator, and serves to bias the actuator to the center, untilted position. The title has been changed to: &#39;&#39;

United States Patent Inventor Eric L. Long Highland Park. Ill.

Appl. No. 724,809

Filed Apr. 29, 1968 Patented Feb. 9, l97I Assignee Cherry ElectricalProducts Corporation Highland Park, III.

a corporation of Illinois TILT SWITCH WITH FLAT SPRING CENTERING MEANS 2Claims, 10 Drawing Figs.

US. Cl

200/153, 200/6, 200/67 Int. Cl H0lh 21/24 Field of Search ZOO/6C, 67,67.7, 159A, 67C. 1661, 5 (Cursory), I54, 172, 1728, 153.10

Primary ExaminerRobert K. Schaefer Assistant ExaminerRobert A. VanderhyeAttorney-Edward C. Threedy ABSTRACT: A switch having a tiltable actuatorfor pivoting a switch blade about a pivot terminal post in a make andbreak movement with respect to a pair of associated terminal contacts. Aflat spring engages a cooperating flat portion on the bottomside of theactuator, and serves to bias the actuator to the center, untiltedposition.

The title has been changed to: Tilt Switch With Flat Spring CenteringMeans."

TILT SWITCH WITH FLAT SPRING CENTERING MEANS SUMMARY OF THE INVENTION Aswitch, including a housing for a plurality of terminal contacts, withone of the terminal contacts providing a fulcrum for a tiltable switchblade; a preformed switch blade so arranged as to have its opposite endsmovable into and out of contact with certain of the terminal contactswhen the blade is tilted about the fulcrum. A tiltable actuator mountedon the housing in a neutral position, and having an actuating element incontact with the tiltable blade, and in operative relationship to thefulcrum provided by one of the terminals to effect tilting of the bladethereabout, as the actuator is tilted in either direction out of itsneutral position against a spring that yieldably maintains the actuatorin its neutral position.

The invention consists in the novel combination and arrangement of partsto be hereinafter described and claimed.

The invention will be best understood by reference to the accompanyingdrawings showing one form of construction and in which:

FIG. 1 is a perspective view of the tilt switch;

FIG. 2 is a side elevational detailed view of the tilt switch in itsneutral position;

FIG. 3 is a side elevational detailed view of the switch in one actuatedposition;

FIG. 4 is a plan underside view of the switch actuator;

FIG. 5 is a top plan view of the tilt switch with the actuator removed;

FIG. 6 is a side elevational view of the actuator;

FIG. 7 is a perspective view of the fulcrum terminal post;

FIG. 8 is a perspective view of one of the switch blades of the switch;

FIG. 9 is a schematic circuit representing the different operations ofthe tilt switch; and

FIG. 10 is a schematic circuit representing the different operations ofmodified tilt switch.

The tilt switch 10 as shown in FIG. 1 provides a hollow base 11 having aportion thereof covered by a protective sleeve 12. A tiltable actuator13 is pivotally mounted on a pin shaft 14 extending between triangularlyshaped side walls 15 and 16 of the base 11. The base 11 also providesend walls 17 and 18 which together with the sidewalls 15 and 16 define acenter cavity 19.

Extending through the bottom wall 20 of the base 11 are a plurality ofaligned tenninals 21, 21' and 21 as well as parallelly alignedcorresponding terminals 22, 22 and 22". d

The terminals 21 and 22' are of the construction shown in FIG. 7, and assuch each provides a fulcrum 23.

The switch 10 as shown in the drawings includes two switch blades 24 and25. Each of the switch blades 24 and 25 are of a similar constructionand one is more specifically. shown in FIG. 8 wherein the blade 24 has acontact bearing end 26, and its opposite end reversely bent as at 27 soas to provide a yieldable finger 28 which terminates into an angular tab29. The medial portion of the blade has formed therein an invertedV-shaped seat 30 which is adapted to sit on the fulcrum head 23 ofeither of the terminals 21 or 22. As shown in FIG. 5 the switch blades24 and 25 are reversely positioned within the cavity 19 so that aspecific operation may be achieved and which is hereinafter explained.The yieldable actuator 13 has, as shown in FIG. 4, its underside 31formed to provide a center block 32 which includes side edges 33 as wellas triangularly shaped pivot bearings 34 and 35, which pivot bearingshave their apexes offset horizontally with respect to each other asclearly shown in FIG. 6. The center block 32 also provides a centersupport 36 having a substantial flat surface, which lies below thehorizontal plan of the side edges 33 as seen in FIG. 6.

The end walls 17 and 18 of the base 11 are provided with posts 37 and 38which form recesses 39 which in turn receive the opposite ends of a flatspring 40. When the actuator 13 is mounted between the sidewalls 15 and16 the flat surface of the center support 36 of the center block 32formed on underside 31 thereof will lie in facial abutment on the flatspring 40 as seen in FIG. 2, maintaining the switch 10 in its neutralposition. To actuate the switch so as to establish a circuit throughcertain of its terminals and switch blades. the actuator l3 may bepivoted in either a clockwise or anticlockwise direction about the pinshaft 14 as viewed in FIGS. 2 and 3. As specifically shown in FIG. 3 theactuator 13 has been tilted about the pin shaft 14 in a clockwisedirection and this movement has caused the triangularly shaped pivotbearing 34 to move against the yieldable finger 28 of the switch blade24 to a position where its line of force upon the yieldable finger 28extends to the opposite side of the fulcrum head 23 causing the blade 24to pivot thereabout into the position shown in FIG. 3. At the same timepivot bearing 35 has been moved further along the finger portion ofblade 25 to maintain it in its unactuated position. In the pivotedposition of the blade 24. as shown in FIG. 3, its contacting end 36 hasbeen moved into contact with the terminal head 41 of the terminal 22while its opposite end 27 has been pivoted out of contact with thecontact head 42 of the terminal 22 In the event the actuator 13 istilted in an opposite direction, the other oppositely disposed switchblade 25 will pivot about its fulcrum 23 when the pivot bearing 35 movesagainst the yieldable finger 28 of the switch blade 25.

The operation of the switch 10 is schematically shown in FIG. 9 whereinthe uppermost diagram illustrates the tilt switch 10 in its neutralposition. In such a position the switch blade 24 is depicted as making aconnection between terminal 22' and terminal 22" while switch blade 25is shown as completing a circuit between terminals 21 and 21 The tiltingmovement of the actuator 13 effects the change in circuitry asillustrated in the second diagram of FIG. 9 wherein switch blade 24 hasnow been pivoted about its fulcrum so that it now makes contact betweentenninals 22' and 22 while switch blade 25 has not been affected by themovement of the actuator 13. If, however, the actuator 13 is pivoted inan anticlockwise direction from its position as shown in FIG. 2, thenthe third diagram of FIG. 9 depicts the circuitry established by thepivotal movement of the switch blade 25.

A switch embodying the structural characteristics as heretoforedescribed but employing only two sets of two terminals each is depictedby the schematical circuitries of FIG. 10. In such an arrangement thetwo switch blades are positioned to have their contact endsjuxtapositioned in one end of the housing, and have the pivot bearingson the actuator reversed from that shown in FIG. 6. Upon tiltablemovement of the actuator in one direction the one blade 24' will bemoved from its position shown in the first diagram of FIG. 10 and bedisconnected from the terminals 50 and 50 will make a circuit as shownin the second diagram of FIG. 10. In the event the actuator is tilted inan opposite direction both switch blades 24 and 25 will make a circuitconnection between their respective terminals 50 and 50' and 51 and 51'.

While I have illustrated and described the preferred fonn ofconstruction for carrying my invention into effect, this is capable ofvariation and modification without departing from the spirit of theinvention. I, therefore, do not wish to be limited to the precisedetails of construction set forth, but desire to avail myself of suchvariations and modifications as come within the scope of the appendedclaims.

I claim:

1. A momentary electrical tilt switch having an open housing providing acenter cavity and including a plurality of terminals extending throughone wall of the housing and providing head portions within the cavitywith certain head portions of a pair of the plurality of terminalsproviding juxtapositioned pivot seats for a plurality of switch blades,wherein the improvement comprises:

a. an actuator pivotally connected to the housing for tiltable movementin opposite directions;

b. first and second elongated switch blades each positioned upon one ofthe pivot seats within said cavity and each providing a contact-bearingand extending in opposite directions and to either side of the pivotseats;

c. said switch blades each providing at their opposite ends a yieldablearm reversely bent with respect to their longitudinal axis and of alength such that their free ends project over and beyond theirrespective pivot seats;

d. actuating members on the bottom of said actuator for each of saidswitch blades, with each actuating member spaced laterally andhorizontally from each other so as to contact said yieldable arms ofsaid switch blades inwardly of their free ends and at a point onopposite sides of their respective pivot seats so as to maintain each ofsaid switch l blades in an unbalanced condition;

e. a flat spring within the housing extending parallelly between saidswitch bladesand in an elevated plane with respect thereto and incontact with a flat portion on the bottom of said actuator between saidactuating members wherein said actuating members are inverted'triangularly shaped pivot bearings depending from the bottom of saidactuator to either side of the flat portion thereof that is in contactwith said flat spring and having their apexes in sliding contact withsaid yieldable arms of said switch blades.

for yieldably maintaining said actuator in an untilted posi- UNITEDSTATES PATENT OFFICE CERTIFICATE OF CORRECTION PatentfNo. 3,562,462Dated FeBruayy 9, 1971 Inventofls) E L Long It is certified that errorappears in the above-identified paten' and that said Letters Patent arehereby corrected as shown below:

Column 2, line 74, "and" should read end Signed and sealed this 14th dayof January 1975.

- (SEAL) Atteat:

MCCOY M. GIBSON JR. C. MARSHALL DANN Attesting Officer Commissioner ofPatents FORM PO-1D50 (10-69) uscoMM-Dc u

1. A momentary electrical tilt switch having an open housing providing acenter cavity and including a plurality of terminals extending throughone wall of the housing and providing head portions within the cavitywith certain head portions of a pair of the plurality of terminalsproviding juxtapositioned pivot seats for a plurality of switch blades,wherein the improvement comprises: a. an actuator pivotally connected tothe housing for tiltable movement in opposite directions; b. first andsecond elongated switch blades each positioned upon one of the pivotseats within said cavity and each providing a contact-bearing andextending in opposite directions and to either side of the pivot seats;c. said switch blades each providing at their opposite ends a yieldablearm reversely bent with respect to their longitudinal axis and of alength such that their free ends project over and beyond theirrespective pivot seats; d. actuating members on the bottom of saidactuator for each of said switch blades, with each actuating memberspaced laterally and horizontally from each other so as to contact saidyieldable arms of said switch blades inwardly of their free ends and ata point on opposite sides of their respective pivot seats so as tomaintain each of said switch blades in an unbalanced condition; e. aflat spring within the housing extending parallelly between said switchblades and in an elevated plane with respect thereto and in contact witha flat portion on the bottom of said actuator between said actuatingmembers for yieldably maintaining said actuator in an untilted position;f. said actuating members movable with said actuator so as to repositionthe downward contact force of either one of said actuating members ontothe free end of said yieldable arm of one of said switch blades at apoint to the other side of the pivot seat to pivot the contact-bearingend of said switch blade into contact with a head portion of one of theterminals.
 2. A momentary electrical tilt switch as defined by claim 1,wherein said actuating members are inverted triangularly shaped pivotbearings depending from the bottom of said actuator to either side ofthe flat portion thereof that is in contact with said flat spring andhaving their apexes in sliding contact with said yieldable arms of saidswitch blades.